ATLANTA — Fears of a coming economic collapse that could spark widespread violence, even civil war, fueled the continued explosive growth of conspiracy-minded antigovernment “patriot” groups in 2011.

That's the conclusion of a new report from the Southern Poverty Law Center, which tracks extremist groups in the United States. The organization's quarterly Intelligence Report, issued Thursday, found that the number of patriot groups grew from 824 to 1,274 between 2010 and 2011, up from 149 in 2008.

Earlier analysis by the SPLC, headquartered in Montgomery, Ala., found that the patriot movement was largely inspired by concerns that whites would become a minority in the US by mid-century – symbolized by the election of President Obama, the nation's first black president, in 2008. Now, however, the movement is also drawing energy from conspiracy theories about globalization, the loss of individual rights and opportunity, and economic doom.

“The animus toward Obama and the government may be as much rooted in economic as racial anger,” Mr. Potok writes in the report, adding later at a press conference that, “This is largely a national reaction to things that are going on in the real world.”

The SPLC says it doesn't track political opposition groups, only those that espouse invalidated conspiracy theories in order to gin up fear and drive membership.

“They tend to have the groups in there where people are either espousing really extremist rhetoric or they've got connections to illegal behavior,” says Carolyn Gallaher, author of “Fault Line: Race, Class and the American Patriot Movement.”

“But the patriot movement is a huge umbrella,” she says, “and there are many people that are in that movement that aren't engaged in illegal activity.”

In its report, the SPLC says that the normalizing of conspiracy theories, largely a result of the breakdown in traditional media and rise of the blogosphere, has played into the growth of patriot groups as their ideas have gained traction in the political sphere, including on many US city councils and county commissions.

Specific ideas include pushback to the United Nations Agenda 21 “smart growth” treaty; lingering questions about Mr. Obama's citizenship, highlighted last week by an independent investigation into Obama's eligibility by Sheriff Joe Arpaio in Arizona; whispers about FEMA building concentration camps; rumors of covert plans by Mexico to repatriate parts of the Southwest; and concerns about Muslim Sharia law becoming part of the US court system.

Patriot groups are also pushing state legislation to rebuff the National Defense Authorization Act, signed by Obama in December, which allows the US to detain without arrest American citizens believed to be involved in terrorism, which is widely seen in the patriot community as a constitutional breach.

All those factors taken together – fears about government tyranny, the looming loss of the white majority, degradation of economic opportunity, the political and media mainstreaming of more extremist thought, and the potential reelection of Obama – have served to “drive up the danger level,” Potok says.

Along with the rise in patriot groups has been a marked increase in gun sales and concealed carry permits, which experts peg in part to crime fears, but also “a basic fear of government, particularly the national government, and what it might do,” says Sanford Levinson, a law professor at the University of Texas, in Austin.

The Department of Homeland Security and the FBI have warned recently about the rise of right-wing extremists and so-called “sovereign citizen” groups, which believe that most US law doesn't apply to them. But those warnings have also served to stoke paranoia among patriot group members.

Those within the largely rural patriot movement agree with the SPLC that tensions are rising ahead of the presidential election in November.

“The worse the economy gets, the more the groups are going to grow,” August Kreis, a former Aryan Nations leader, told the Intelligence Report. “White people are arming themselves – and black people, too. I believe eventually it’s going to come down to civil war. It’s going to be an economic war, the rich versus the poor. We’re being divided along economic lines.”

In his press conference Thursday, Potok quoted League of the South president Michael Hill at a recent talk, where he reportedly said, “We're already at war, what would it take to get you to fight?”

He also quoted William Gheen, head of the Americans for Legal Immigration PAC, as saying that to save “white America” it may be necessary to engage in “extrapolitical activities that I can't really talk about because they're all illegal and violent.”

“I think the growth of patriot groups is a symptom of some very hard times economically and some disturbing political trends,” says Mr. Hill, reached by the Monitor Thursday. “I'm really concerned about the level of animosity between the two sides out there, and that's why I'm saying that people should take advantage of the Second Amendment and make sure they learn to safely use firearms, just to protect themselves in this kind of environment.”

The real concern behind the rise in the number of patriot groups, however, is not always the prospect of crime and violence, but their effect on the political system, says Ms. Gallaher, who is also a professor at American University.

Within these groups, “it's not about race or class, it's always race and class all blended together,” she says. “So we can get caught up on whether or not we label them racist or not, but that's a semantic issue. The real issue is, what are they espousing, and what would it do to minorities and immigrants and the poor?”